LIFTING DEVICE FOR MANIPULATING A TRACK ELEMENT

Abstract: A lifting device for manipulating a track element is intended for handling the track element at a manipulating location at least partially above a track (2) by means of lifting elements (4) and transfer elements (5) included in a lifting device frame (3) and operated preferably by a pressure medium, said frame (3) being provided with power and drive means (6), such as a hydraulic gear and a control centre. The frame (3) includes most preferably two successive pairs (p1, p2) of support members (7), extensible in a transverse direction (x) of the frame (3) and being provided with transfer elements (5), such as wheels, crawlers or the like, for maneuvering the frame (3) on the ground. Thus, most preferably in both pairs the frame (3) is provided with substantially transverse telescopic arms (7a), situated successively in a longitudinal direction (s) of the frame (3) and intended for extending the support members (7). At least one pair (p) consisting of the support members (7) is secured to the lifting device by means of a common subframe (8), which is movably mounted on the lifting device frame (3) for enabling a joint action, such as a tilting action (wx, ws) and/or a rotating action (wz), for the pair (p) formed by the support members (7).

Description: Lifting device for manipulating a track element The present invention relates to a lifting device for manipulating a track element, said lifting device being adapted for transport to a manipulating location on a transport platform included in a transport vehicle and intended for handling a track element at the manipulating location at least partially above the track in vertical and horizontal direction by means of lifting elements and transfer elements, included in a lifting device frame and operated by an auxiliary force, preferably a pressure medium, said frame being further provided with power and drive means, such as a hydraulic gear and a control centre or the like. The frame is fitted with at least one, preferably two pairs of support members, which are successive in the longitudinal direction of the frame and extensible in the transverse direction of the frame and provided with said transfer elements, such as wheels, crawlers or the like for maneuvering the frame on the ground whereby, in view of extending the support members, the frame is fitted with substantially transverse telescopic arms situated successively in the longi- tudinal direction of the frame. In the transport condition, the transfer elements included in the lifting device mounted on a transport platform are retractable essentially upon the transport platform and extensible substantially beyond the transport platform for the operating condition. A lifting device partially of the above type is prior known e.g. from the published application DE-2309930. This publication discloses a lifting device which is provided with a single pair of parallel crawlers operable in vertical direction relative to the lifting device. The lifting elements of this particular lifting device further include separate lifting cylinders for solidly supporting the lifting device on the ground for lifting operations or lateral transfer operations. The lifting device further includes flanged wheels for carrying the lifting device on a track, e.g. for bringing it to a manipulating location, said flanged wheels further providing a support for a track element to be handled during the manipulation thereof. Furthermore, the published application DE-3419240 discloses a lifting device slightly different from that described above, particularly intended for transport to a manipulating location on a transport platform included in a trackbound transport vehicle. In the transport operation, the crawlers of a lifting device mounted on the transport platform are retract- able upon the transport platform and extensible beyond the transport platform for the manipulating opera¬ tion. Moreover, US Patent 5127335 discloses a lifting device distinctively different from those described above, wherein the support members are fastened by the ends thereof in an articulated fashion to a frame located on the centre axis of the lifting device, said support members including crawlers adapted to be pivotable in horizontal plane. In addition, the lifting deive frame is provided in its mid-section with a pivot joint, enabling the turning of the lifting device ends in the longitudinal direction to a certain angle relative to each other. The solution set forth in the published application DE- 2309930 comprises a pair of crawlers coupled directly to a frame carrying the track elements. Thus, the handling of even the most common track elements requires the use of two successive lifting devices, which of course further requires a linkage between the lifting devices for their synchronized operation. The synchronization of separate lifting devices, e.g. for operating the same at sufficiently matching speeds, may cause major problems as well known in the art. In addition, the directional stability of the above type of solutions, especially when using two separate lifting devices, is questionable and, thus, the transfer of a track element to be manipulated e.g. in a given longitudinal direction requires continuous surveillance and correction of the advancing direction. The control of lifting devices of the above type in the advancing direction is conventionally effected in such a manner that the parallel crawlers are operated at relatively different speeds. Thus, when controlling the first one of two separate successive lifting devices, the second lifting device must be controlled the way that corresponds to the first one. In practice, such control is impossible to perform sufficiently well due to technology, surrounding conditions etc. , as both the lifting devices and the manipulated track element are subjected to unreasonable stresses. In the lifting device set forth in the published application DE-3419240, the pairs of crawlers are movably mounted on their own chassis, which are connected thereabove by a lengthwise frame supporting the track elements. The high position of the frame may impair stability of the device and handling of the track elements. In the solution set forth in the above-mentioned US Patent 5127335, the pair of crawlers mounted succes¬ sively in the longitudinal direction is coupled integrally to a common frame. However, the solution described in the cited patent is not very beneficial in practice, since the support members are in an articulated fashion connected by the ends thereof to the frame and, thus, said support members as well as the articulations are subjected to major moments of force. A pivot joint provided in the middle of the frame of a lifting device is preferred in the sense that it enables the self-operated positioning of especially the trailing pair of crawlers upon the manipulation of a track element. In practice, the controllability of this particular solution is probably questionable due to the articulation of support members. Thus, for example, the setting of support members included in the frame in alignment with each other in the same position requires high precision from individual actuators controlling said support members. Even a minor relative angular change in the support members requires continuous corrective measures for maintaining a desired traveling direction when operating the lifting device in longitudinal direction. A lifting device of this invention has an object of providing a decisive improvement over the above- mentioned drawbacks and hence to substantially raise the existing state of the art. In view of fulfilling this object, a lifting device of the invention is principally characterized in that at least one pair consisting of support members is mounted on the lifting device by means of a common subframe, which is movably mounted on the frame of the lifting device for enabling a joint action, such as tilting action and/or rotating action, for the pair consisting of support members. The most important benefits gained by a lifting device of the invention include the simplicity of its con¬ struction and operation and reliability in operation. The lifting device enables the manipulation of track element conveniently in contact with the track whereby, for example, the lifting device can be lowered by means of its own lifting elements from its supporting transport platform directly into contact with the track. Capacity of the lifting device can be dimen¬ sioned optimally as the lifting and transfer actions are effected in a preferred fashion and, thus, the lifting device is not required to have excessive capacity, which would be a result of unfavourable moments and lifting actions. Especially, when using a lifting device provided in longitudinal direction with two successive pairs consisting of support members, the operation of the lifting device will be ideal e.g. in terms of controllability since, depending on the conditions, the rearward pair is capable of positioning itself self-sufficiently upon the manipula¬ tion of a track element. Thus, a lifting device of the invention enables the manipulation of track elements while in contact with the track in such a manner that, on the one hand, a track element can be readily transferred e.g. longitudinally or transversely of the track and, on the other hand, it can be moved in vertical or horizontal plane by seating the lifting device solidly on the ground. The dependent claims directed to a lifting device set forth some preferred embodiments for a lifting device of the invention. In the following specification the invention will be described in detail with reference made to the accom¬ panying drawings, in which Fig. 1 shows a side view of one preferred lifting device of the invention mounted on a transport platform, Fig. 2 is an end view of a corresponding lifting device, Fig. 3 shows a plan view of a pair consisting of support members, Fig. 4 shows a corresponding pair in an end view, Fig. 5 is a cross-sectional view of a bracing element arrangement used in the above- mentioned pair, and Fig. 6 shows a longitudinal section of one preferred control alternative for a lifting device. Referring to Figs. 1 and 2, a lifting device intended for the manipulation of a track element is transported to a manipulating location on a transport platform 1 included in a transport vehicle. The lifting device is intended alone or together with another or a plurality of lifting devices for handling one or a plurality of track elements at a manipulating location above a track 2 in vertical and horizontal direction by means of lifting elements 4 and transfer elements 5, included in a lifting device frame 3 and operated by an auxiliary force, preferably a pressure medium. For this purpose, the frame 3 is further provided with power and drive means 6, such as a hydraulic gear and a control centre or the like. The frame 3 is provided with at least one, preferably, as shown in Fig. 1, two successive pairs p 1 , p 2 of support mem¬ bers 7 in a longitudinal direction s of the frame, said members being extensible in a transverse direction x of frame 3 and provided with said transfer elements 5, such as wheels, crawlers or the like, for carrying the frame on the ground. Thus, in view of extending the support members 7, the frame 3 is provided in each pair p. , p 2 with substantially transverse tele- scopic arms 7a, mounted successively in the longitu¬ dinal direction s of frame 3 and placed on top of the lengthwise frame 3. The lifting elements 4, capable of supporting, lifting and lowering the entire lifting device, are also connected to transverse telescopic arms 4a mounted on top of the frame 3 for shifting said elements in lateral direction. Figs. 1 and 2 further illustrate laterally movable grippers 10 mounted below the lengthwise frame 3 for gripping track elements to be handled. In the transport condition, as shown in Fig. 2, the transfer elements 5 for a lifting device placed on the transport platform 1 are in a retracted condition on top of the transport platform 1 and extensible beyond the transport platform 1 for the operating condition. According to Figs. 3-5, a pair p consisting of support members 7 mounted on the opposite sides of the frame of the lifting device is secured to the lifting device frame 3 by means of a common subframe 8, connecting the successively situated telescopic arms 7a for an integral frame structure, the subframe being movably mounted on the frame 3 for enabling the joint action, such as a tilting action wx, ws and/or a rotating action wz for the pair p consisting of support members 7. Thus, the frame 3 extends below frame structures made up by the telescopic arms 7a of successive pairs p 1 , p 2 . Referring particularly to Figs. 3—5, the transfer elements 5 for the lifting device are adapted to be movable relative to support members 7 by means of elevating members 7b, fitted between support members 7 and transfer elements 5, by moving the transfer ele¬ ments 5 in a substantially vertical direction h e.g. for changing the ground clearance of the lifting device frame 3. In addition and especially in reference to Fig. 3, the lifting device includes directional elements 9 for enabling the rotation of transfer elements 5 in horizontal plane and locking the same in a new position for replacing the traveling direction of the lifting device with a direction different from the longitudinal direction s of the lifting device. For example, the crawlers serving as transfer elements can be turned to a right angle relative to the longi- tudinal direction s, whereby the lifting device can travel sideways. The subframe 8 connecting the support members 7 is linked in a force-transmitting fashion to the lifting device frame 3 by means of a brace element 8a, supporting in substantially vertical direction h the pair p formed by support members 7 and enabling its tilting action wx, ws and rotating action wz. Thus, the frame 3 is capable of tilting about two horizontal axes perpendicular to each other and rotating in horizontal plane about a vertical axis relative to subframe 8. Especially with reference to Fig. 5, said brace element 8a comprises a ball joint, which is located at the centre point K of the pair p consisting of support members 7 substantially on the centre axis of the lifting device. As shown in Fig. 4, the subframe 8 is fastened e.g. by welding to the bottom surface of telescopic arms 7a, whereby the pair p consisting of support members 7 is braced to the lifting device by means of a ball joint 8a fitted between subframe 8 and a backing frame T included in the lifting device frame 3. Especially with reference to Figs. 3 and 4, the lifting device frame 3 includes two primary beams 3a, spaced from each other and extending substantially in longi¬ tudinal direction s of the lifting device, said beams being linked to each other by one or a plurality of secondary beams 3b extending in transverse direction x. Thus, the ball joint 8a is supported on the transverse backing frame T bracing against the centre point of the secondary beam 3b linking said primary beams 3a in the lifting device frame 3. In a further preferred embodiment, at least one pair p consisting of support members 7 is coupled to the lifting device frame 3 by means of at least one elastic element 8b enabling the tilting action wx, ws and/or rotating action wz for said pair p relative to the lifting device frame 3. Said elastic element 8b is most preferably adapted to be self-operated by a spring force whereby, on the one hand, it enables the movement of the pair p formed by support members 7 and, on the other hand, urges to reassume the original position of said pair p relative to the lifting device frame 3. In a preferred embodiment, the elastic element 8b comprises preferably a rubber or metal spring or the like for enabling the tilting action ws, wx and rotating action wz for said pair p, said spring urging progressively, i.e. by a force proportional to the amount of deflection of said pair, to reassume the original position of said pair. Especially with reference to Figs. 3 and 4, the pair p formed by support members 7 is provided with four elastic elements 8b which are mounted at corners essentially on each side of the lifting device. In the illustrated embodiment, the elastic elements 8b are placed away from said pair p in opposite directions in the longi¬ tudinal direction s, more particularly between primary beams 3a and brackets 8c extending from its telescopic arms 7a. The change of direction for transfer elements 5 can also be effected by means of hydraulic cylinders, as shown in Fig. 6. The top surface of elastic elements 8b mounted below the brackets 8c is provided with plastic slide plates, enabling the sliding thereof relative to telescopic arms 7a. The springs are held in position by means of pins secured to the top surface of primary beams 3a. The pair p is turned in horizontal plane relative to the frame 3 by means of two hydraulic cylinders 11 fitted between primary beams 3a and subframe 8, said cylinders being controlled by means of a single control valve. The system includes also a linear gauge trans¬ ducer 12, providing continuously information about the position of the pair p of support members 7 and, as a consequence, that of transfer elements 5 relative to the frame 3. The hydraulic valve receives the control information from a joystick included in the operator's controller and also from the linear trans¬ ducer. By comparing such information, the system automatically urges to maintain the direction of the transfer elements, such as crawlers, in the direction corresponding to the control stick. It is obvious that a lifting device of the invention is not limited to the above-described embodiments but can be subjected even to major modifications within the scope of the basic idea. Naturally, a lifting device of the invention can be fitted with separate flanged wheels for transferring the lifting device along an existing track, whereby a track element to be removed can be supported against said wheels. It is not absolutely necessary to provide a lifting device of the invention with separate lifting ele¬ ments 4, as shown in Fig. 1, which are braced on the ground and operated in vertical direction relative to the frame 3 by means of lifting cylinders 4b. The lifting action effected by lifting elements 4 can be replaced by providing a more extensive movement in vertical direction for the elevating members 7b, such as hydraulic cylinders, operating said transfer elements 5. In this case, however, it is not possible to brace the lifting device solidly on the ground, for example in such a manner that it would be possible to transfer the lifting device in lateral direction by supporting the lifting device alternately on lifting elements 4 and transfer elements 5. In addition, the separate lifting cylinders 4b enable that the direc¬ tional elements 9 of transfer elements 5 be re-directed while the lifting device is supported upon the lifting cylinders. Naturally, when one and the same working operation is performed by using two or more lifting devices, the lifting devices are preferably adapted to operate on a so-called slave linkage, whereby a single action of a lifting device is used for passively controlling the other lifting devices. Such arrangements can be adapted to operate e.g. on a transceiver principle or in a corresponding fashion.

Claims: Claims 1. A lifting device for manipulating a track element, said lifting device being adapted for transport to a manipulating location on a transport platform (1) included in a transport vehicle and intended for handling a track element at the manipulating location at least partially above a track (2) in vertical and horizontal direction by means of lifting elements and transfer elements (5) , included in a lifting device frame (3) and operated by an auxiliary force, prefer¬ ably a pressure medium, said frame (3) being further provided with power and drive means (6) , such as a hydraulic gear and a control centre or the like, said frame (3) being equipped with at least one, preferably two pairs (p; p 1 , p 2 ) of support mem¬ bers (7) , which are successive in the longitudinal direction (s) of the frame (3) and extensible in the transverse direction (x) of the frame (3) and provided with said transfer elements (5) , such as wheels, crawlers or the like for maneuvering the frame (3) on the ground whereby, in view of extending the support members (7) , the frame (3) is equipped in at least one pair with substantially transverse telescopic arms (7a) situated successively in the longitudinal direction (s) of the frame (3) whereby, in the trans¬ port condition, the transfer elements (5) of a lifting device situated on the transport platform (1) are retractable essentially upon the transport platform (1) and extensible substantially beyond the transport plat¬ form (1) for the operating condition, characterized in that at least one pair (p) consisting of the support members (7) is mounted on the lifting device by means of a common subframe (8) , which is movably mounted on the frame (3) of the lifting device for enabling a joint action, such as tilting action (wx, ws) and/or rotating action (wz) , for the pair (p) consisting of the support members (7) . 2. A lifting device as set forth in claim 1, charac¬ terized in that the frame (3) is mounted below a structure linking the support members (7) of the pair (p) transversely to each other. 3. A lifting device as set forth in claim 1 or 2, whereby the transfer elements (5) are adapted to be movable relative to the support members (7) by moving the transfer elements (5) by means of elevating mem- bers (7b) in a substantially vertical direction (h) at least for changing the ground clearance of the lifting device frame (3) and/or by using directional elements (9) for rotating the transfer elements (5) in a substantially horizontal plane for replacing the traveling direction of the lifting device with a direction different from the longitudinal direction (s) of the lifting device, characterized in that the subframe (8) connecting the support members (7) is linked in a force-transmitting fashion to the lifting device frame (3) by means of at least one brace element, supporting in a substantially vertical direction (h) the pair (p) formed by the support members (7) and enabling its tilting action (wx, ws) and rotating action (wz) . 4. A lifting device as set forth in claim 3, charac¬ terized in that said brace element (8a) comprises at least one ball joint or a like, which is fitted at the centre point (K) of the pair (p) formed by the support members (7) substantially on the centre axis of the lifting device. 5. A lifting device as set forth in claim 3 or 4, characterized in that the subframe (8) is fastened preferably by welding or in a like manner to the bottom surface of the telescopic arms (7a) , whereby the pair (p) consisting of the support members (7) is adapted to be at least partially braced to the lifting device by means of the brace element (8a) fitted between the subframe (8) and a backing frame (T) included in the lifting device frame (3) . 6. A lifting device as set forth in any of the preceding claims 1-5, whereby the lifting device frame (3) includes at least two primary beams (3a) , spaced from each other and extending substantially in the longitudinal direction (s) of the lifting device, said beams being linked to each other by one or a plurality of secondary beams (3b) extending in the transverse direction (x) , characterized in that the brace element (8a) is supported on the backing frame (T) bracing substantially against the centre point of one or more secondary beam (3b) linking said primary beams (3a) in the lifting device frame (3) . 7. A lifting device as set forth in any of the preceding claims 1-6, characterized in that the pair (p) consisting of the support members (7) is adapted to be at least partially coupled to the lifting device frame (3) by means of at least one elastic element (8b) enabling the tilting action (wx, ws) and/or rotating action (wz) for said pair (p) relative to the lifting device frame (3) . 8. A lifting device as set forth in claim 7, charac¬ terized in that said elastic element (8b) is adapted to be self-operated, preferably by a spring force whereby, on the one hand, it enables the movement of the pair (p) formed by the support members (7) and, on the other hand, urges to reassume the original, preferably adjustable position of said pair (p) relative to the lifting device frame (3) . 9. A lifting device as set forth in claim 7 or 8, characterized in that the elastic element (8b) com¬ prises preferably a rubber or metal spring or the like for enabling the tilting action (ws, wx) and rotating action (wz) for said pair (p) , said spring urging progressively, i.e. by a force proportional to the amount of deflection of said pair (p) , to reassume the original position of said pair (p) . 10. A lifting device as set forth in any of the preceding claims 7-9, characterized in that at least two elastic elements (8b) mounted in connection with at least one pair (p) formed by the support members (7) are positioned essentially on each side of the lifting device, preferably substantially in connection with the primary beams (3a) . 11. A lifting device as set forth in any of the preceding claims 7-10, characterized in that at least one pair (p) formed by the support members (7) is provided with four elastic elements (8b) which are mounted at corners essentially on each side of the lifting device, preferably between the primary beams (3a) and brackets (8c) extending from said pair (p) in directions opposite to each other in the longitudinal direction (s) . 12. A lifting device as set forth in any of the preceding claims 1-10, characterized in that, in view of controlling the transfer elements (5) , between the frame (3) and the subframe (8) is fitted an actuator, such as a hydraulic cylinder (11) , preferably a pair of hydraulic cylinders (11) on either side of a vertical axis defining the rotating action (wz) and on the opposite sides of the frame (3) .

Inventors: KOIVISTO SEPPO, MUSTASILTA TIMO, VENAELAEINEN EINARI, KOIVISTO, SEPPO, MUSTASILTA, TIMO, VENAELAEINEN, EINARI
Applicants: DESEC INSTMSTO, KOIVISTO SEPPO, MUSTASILTA TIMO, VENAELAEINEN EINARI, INSINOEOERITOIMISTO DESEC OY, KOIVISTO, SEPPO, MUSTASILTA, TIMO, VENAELAEINEN, EINARI
Application year: 1994
Main classification: E01B29
IPC codes: E01B29